1. Field of the Invention
The present invention generally relates to a plug-in module, and more particularly to a plug-in module used for high-speed transmission.
2. Description of Related Art
SFP (Small Form-factor Pluggable), X-SFP and QSFP are all modules for fiber optic transmission or signal transmission. All of the modules are of small size or form factor which is important. The smaller the form factor of the module, the less space taken on a printed circuit board to which it couples. A smaller form factor allows a greater number of modules to be coupled onto a printed circuit board to support additional communication channels. However, the smaller form factor makes it more difficult for a user to handle.
When such a module embedded in a system fails, it is desirable to replace it, particularly when other communication channels are supported by other modules. To replace a failed module, it needs to be pluggable into a module receptacle. While, plugging in a new module is usually easy, it is more difficult to remove the failed module because of other components surrounding it. Additionally, a user should not attempt to pull on cables of the module in order to try and remove a failed module or else the user might cause damage thereto.
A typical release method for a pluggable module is to push in on the module itself and then pull out on the module to release it from a cage assembly or module receptacle. It has been determined than this method is not very reliable with users complaining of the difficulty in removing pluggable modules in such manner. Users often complain that traditional methods offer little leverage in getting a sufficient grip on the module when attempting to pull it out of a module receptacle. Another complaint is that traditional actuators used to remove modules are inaccessible or invisible. Other users complain than once released by the traditional method, it is difficult to withdraw the module out of its cage or module receptacle.
Therefore, designers developed different solutions to solve above problems accounted by the users, such as disclosed by U.S. Pat. Nos. 6,851,867, 6,749,448, 6,884,097, 6,908,323, 7,052,306, 6,824,416 and 7,090,523. The theories of theses patents are substantially the same, that is each module is received in corresponding cage or module receptacle and comprises a pair of sliders with forward ends engaging with tabs of the cage, and a bail or lever capable of rotating to actuate the sliders linearly to separate forward ends of the sliders from the tabs. The action theory of theses patents successfully solve the problems mentioned above. However, the latch mechanisms disclosed above all need springs to serve as spring back means to actuate the latch mechanisms to return to original positions. Further, the plug-in modules are arranged side by side to mate with module receptacles. There is little space left for operator to pull bail or levers to separate the plug-in modules from the module receptacles. The present invention provides a plug-in module with an improved latch mechanism operating in a theory different from that of these patents while still successfully solving the problems and with self spring back function and an additional pull tape.